Monitoring and control of soil conditions

ABSTRACT

Various methods and systems are provided for monitoring and control of soil conditions. In one example, among others, a method includes obtaining one or more aqueous sample from at least one suction probe within a soil substrate and analyzing the one or more aqueous sample to determine a chemical composition of the soil substrate. Amounts of an additive may be determined to adjust the chemical composition of the soil substrate. In another example, a method includes installing at least one suction probe within a soil substrate; drawing a vacuum to induce hydraulic conduction of at least one aqueous solution from the soil substrate; extracting one or more aqueous sample; and analyzing the one or more aqueous sample to determine a chemical composition.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of application Ser. No.14/755,495, filed Jun. 30, 2015, now U.S. Pat. No. 10,620,180, which isa divisional application of Application Ser. No. 13/654,769, filed Oct.18, 2012, and this application is a continuation application ofapplication Ser. No. 14/755,515, filed Jun. 30, 2015, now U.S. Pat. No.10,663,447, which is a divisional application of application Ser. No.13/654,769, filed Oct. 18, 2012, now U.S. Pat. No. 9,107,341, whichclaims priority to U.S. provisional application entitled “MONITORING ANDCONTROL OF SOIL CONDITIONS” having Ser. No. 61/603,680, filed Feb. 27,2012, all of which are hereby incorporated by reference in theirentirety.

BACKGROUND

As population continues to increase, food production becomes an everexpanding problem. Effective use of water resources affects theproductivity of agricultural farms. In addition, fertilization hasbecome one of the main factors enhancing productivity and quality ofagricultural farms. This has resulted in increased consumption offertilizers worldwide, raising new issues such as increased productioncosts and contamination effects from agricultural activity.

BRIEF DESCRIPTION OF THE DRAWINGS

Many aspects of the invention can be better understood with reference tothe following drawings. The components in the drawings are notnecessarily to scale, emphasis instead being placed upon clearlyillustrating the principles of the present invention. Moreover, in thedrawings, like reference numerals designate corresponding partsthroughout the several views.

FIG. 1 is a graphical representation illustrating the monitoring of thecondition of the soil using a plurality of suction probes according tovarious embodiments of the present disclosure.

FIG. 2 is a graphical representation of an example a suction probe ofFIG. 1 according to various embodiments of the present disclosure.

FIG. 3 is a flow chart illustrating an example of monitoring and controlof the soil condition according to various embodiments of the presentdisclosure.

FIG. 4 is a flow chart illustrating an example of sample analysisaccording to various embodiments of the present disclosure.

FIG. 5 is a table illustrating the relationship between variousadditives and their effect in a plant according to various embodimentsof the present disclosure.

FIG. 6 is a flow chart illustrating an example of the composition and/orutilization evaluation of FIG. 3 according to various embodiments of thepresent disclosure.

FIG. 7 is an example of a system that may be utilized in the monitoringand control of soil conditions according to various embodiments of thepresent disclosure.

DETAILED DESCRIPTION

Disclosed herein are various embodiments related to monitoring andcontrol of soil conditions in, e.g., agricultural applications.Reference will now be made in detail to the description of theembodiments as illustrated in the drawings, wherein like referencenumbers indicate like parts throughout the several views.

Controlled application of water and fertilizers can enhance theproductivity of agricultural farms in a sustainable fashion, providinggreater profitability, food safety, and environmental preservation.Monitoring the nutritional conditions of the crops may be used tocontrol the application of available resources (e.g., water andfertilizer) to fulfill the plants nutritional needs throughout theirevolution; thereby improving productivity and quality of the resultingproduce while reducing inputs and loss through lixiviation.

Analysis of the chemical composition of the soil and/or liquids aboutthe roots of the plants, as well as diagnosis of the plant condition,can provide an indication of nutrient absorption by the plants which maybe used to control watering and/or fertilization. Monitoring of the soilcondition may be accomplished using suction probes installed atdifferent depth levels of the root profiles of the crops. By extractingaqueous solutions from the soil substrate about the roots, theinteraction of the root activity and soil conditions may be monitoredand used to control the application of nutrients to the soil substrate.For example, the reaction and behavior of the inputs (e.g., water,effluents, fertilizers, coadyuvants, chelates, etc.) added to the soiland the reaction of the soil to these inputs, as well as root activityfor nutrient absorption, may be evaluated throughout the phenologicalcycle of the plants to provide indications that may be used forcontrolling the application of additives such as, e.g., chemicalnutrients in a cyclic or continuous manner.

Referring to FIG. 1, shown is a graphical representation illustratingthe monitoring of the condition of the soil 103 using one or moresuction probes 106 according to various embodiments of the presentdisclosure. For example, plants 109 of the same species are planted inthe soil substrate 103 with their roots extending through a rootactivity zone 112. Water and/or fertilizer solutions 115 may be providedto the plants 109 through drip lines, sprinklers, or other deliverysystem. In the example of FIG. 1, suction probes 106 are located at aplurality of depths (or levels) within the root activity zone 112 of theplant(s) 109. For example, suction probes 106 may be placed at twodepths (e.g., about 15 cm and about 30 cm) for vegetable crops or threedepths (e.g., about 20 cm, about 40 cm, and about 60 cm) for woodyplants. Suction probes 106 may also be located at other depths as can beunderstood. The depth(s) may vary based upon the plant species. Inaddition, probes may be installed at a depth below the root activityzone 112 to monitor for propagation of unused nutrients through the rootactivity zone 112. Additional suction probes 106 at the same ordifferent depths may also be utilized. For instance, suction probes 106may be distributed, either individually or in groups, at differentlocations within a row, bed, and/or field to monitor for variationswithin the field.

In other implementations, one or more suction probes 106 may be placedat one or more depths in the soil substrate 103 for environmentalmonitoring such as, e.g., where lixiviation is monitored. For example,in the metal or mining industries where washes and flushing are oftenused, monitoring for metal or other contamination in the soil substrate103 may be implemented using suction probes 106. Possible applicationsmay include, but are not limited to, static leaching, site monitoringfor decontamination, medium and long term monitoring of restorationand/or rehabilitation of affected spaces, leakage and/or spoilagemonitoring, etc. using one or more suction probes to obtains samplesfrom a soil substrate. Aqueous samples may be analyzed for chemicalcomposition to monitor for variations in the soil substrate 103.Remedial or corrective actions may be taken based upon the monitoredsample composition. Analysis of the samples may be used to providewarnings and/or alarms and/or to propose corrective measures toeliminate or reduce the environmental effects.

FIG. 2 illustrates an example a suction probe 106 of FIG. 1. The suctionprobe 106 of FIG. 2 includes a porous capsule 203 of, e.g., porcelainattached to one end of a tube 206 of inert material such as, e.g., hardrubber, polyethylene, or PVC. For example, the porous capsule 203 may beabout 50 mm in diameter and extend from the end of the tube by about 85mm. The porous porcelain may have a thickness of about 5 mm with aporosity of about 25-23% and an average porous diameter of about 8-10 Å.Other chemically inert materials may also be used for the porous capsule203 such as, e.g., porous ceramic. The porous characteristics of thematerial used in the porous capsule 203 allow for hydraulic conductivityof aqueous solutions from the soil when a vacuum is drawn inside thesuction probe 106. The porosity of the porous capsule 203 should allowthe monitored chemical composition to enter the suction probe 106without difficulty. In addition, other shapes and dimensions may also beused for the porous capsule 203 and/or suction probe 106. A cap 209(e.g., rubber or PVC) seals the opposite end of the tube 206. A fitting212 attached to the cap 209 allows for connection to a vacuum pump todraw a vacuum within the hollow suction probe 106. The fitting 212 mayinclude a valve to allow the vacuum pump to be disconnected whilemaintaining the vacuum within the suction probe 106.

Referring back to FIG. 1, the suction probes 106 are installed in avertical position within the soil 103 at a plurality of depths withinthe root activity zone 112. For example, a hole may be drilled into thesoil 103 and the suction probe 106 may be inserted to the appropriatedepth. In general, a group of suction probes 106 are installed in anarea of good root activity under the same plant or under neighboringplants that are in the same phenological stage. For example, a group ofsuction probes may be installed along a crop row of plants that wereplanted together. The location of the suction probes 106 may also takeinto account the position of the irrigation system. For instance, asuction probe 106 may be located in the center of a wet area under adrip line. Also, suction probes 106 should be adequately spaced apart(e.g., about 20-30 cm) to allow room for adequate sampling of aqueoussolutions from the surrounding soil without competing with an adjacentsuction probe 106.

In some implementations, the porous capsules 203 (FIG. 2) of the suctionprobes 106 may be submerged in water (e.g., for about 15-20 minutes) toallow for hydration of the porous capsules 203. Hydration of the porouscapsules 203 can improve the hydraulic connection between the soil 103and the porous capsules 203. Hydration may also facilitate insertion ofthe suction probe 106 into the soil 103. The surrounding soil 103 mayalso be packed around the suction probe 106 (e.g., using a wire) toensure a good hydraulic connection between the porous capsule 203 andthe soil 103. Samples of the soil 103 at various depths (e.g., 0-30 cmand 30-60 cm) may be obtained during installation of the suction probes106. A soil sample may be obtained for each of the probe depths. A soilsampling protocol may be followed to ensure that the samples represent atrue indication of the soil composition. Analysis of the soil samplescan provide base line information about the composition of the soilsubstrate 103.

After installation of the suction probes 106, aqueous solutions may beextracted from the substrate surrounding the roots of the plant(s) bydrawing a vacuum in the suction probes 106. A vacuum pump (not shown)may be connected to the fitting 212 (FIG. 2) to draw a vacuum within ahollow suction probe 106. For example, the vacuum may be in the range ofabout 0.5 atmosphere (atm) to about 1.0 atm, in the range of about 0.6atm to about 0.9 atm, in the range of about 0.7 atm to about 0.8 atm, orabout 0.8 atm. A meter may be used to indicate the vacuum within thesuction probe 106. Once the vacuum has been drawn within the suctionprobe 106, a valve included in fitting 212 may be closed to maintain thevacuum in the suction probe 106. In some cases, the size of the suctionprobe 106 may allow a vacuum to be drawn with a manual pump.

The vacuum within a suction probe 106 hydraulically conducts an aqueoussolution from the surrounding soil 103 into the suction probe 106through the porous capsule 203 (FIG. 2). The volume of the collectedsolution will depend on the hydraulic conductivity of the soil substrate103 and the water content of the soil 103, as well as the extractiontime during which the vacuum is maintained in the suction probe 106. Forexample, the extraction period may be about 2 days to about 4 days.Vacuum conditions and air tightness depends upon porous characteristicsof the material of the porous capsule 203 and the connection with thesurrounding soil 103. In some implementations, the vacuum may bemaintained within a range of values over the extraction period.

At the end of the extraction period (e.g., after about 48 hours), anaqueous sample is collected from the suction probe 106. An aqueoussampling protocol may be followed to ensure that the samples represent atrue indication of the chemical composition of the aqueous sample. Forexample, the aqueous sample may be obtained through a micro tube thatpasses through the open fitting 212 (FIG. 2) to the porous capsule atthe end of the suction probe 106. A syringe (or other extraction device)may be used to extract the aqueous sample from the suction probe 106through the micro tube. Aqueous samples of 30 ml or more may be obtainedand provided for analysis. In some implementations, a 125 ml aqueoussample is obtained. In some embodiments, a separate sampling tube isprovided for obtaining aqueous samples through the cap 209 (FIG. 2) ofthe suction probe 106. The sampling tube may pass through a separatehermetically sealed opening in the cap 209. A valve in the sampling tubemay be used to close off the sampling tube during the extraction period.The valve may then be opened to allow the aqueous sample to be obtainedfrom the suction probe 106. The aqueous samples from the suction probe106 may then be provided for chemical analysis and further evaluation.

In addition to the aqueous samples from the suction probe 106, samplesof a fertilizer solution (FS) 115 (FIG. 1) that is supplied to theplants 109 may be obtained during irrigation of the plants 109 (FIG. 1).The FS 115 includes irrigation water that may be mixed with additivessuch as, e.g., fresh or filtered water, residue water, fertilizers,minerals, chemicals and/or other nutrients. A sampling protocol may befollowed to ensure that the samples represent a true indication of theFS composition. For example, one or more collection device(s) located inthe vicinity of the suction probes 106 collect FS 115 during plantirrigation. A plurality of collection devices may be distributed atdifferent locations within a row, bed, and/or field to monitor forvariations in distribution of the FS 115 within the field. In the caseof drip irrigation, a collection device such as, e.g., an appropriatelysized liquid container may receive FS 115 from the drip line through anadapter near the group of suction probes 106 (FIG. 1). Thus, when theplants 109 are being irrigated, the collection device collects a sampleof the FS 115 being applied. In the case of sprinkler irrigation, acollection device such as, e.g., an open container may be positioned inthe vicinity of the group of suction probes 106 to collect an FS samplefrom the discharge of the sprinkler. These examples provide a sample ofthe FS 115 that is representative of that provided over the entireirrigation time period.

The FS samples may then be provided for analysis. Analysis of the FS 115provides information regarding the fertilizer contributions and theconditions of assimilation (e.g., pH, electrical conductivity, and ionicrelationship). When considered with the aqueous solution analysis andthe soil sample analysis, it is possible to evaluate the interaction ofthe FS 115 with the plant 109 and soil 103 (FIG. 1). For example, plantabsorption and/or utilization of nutrients as well as soil interactionssuch as precipitation, solubility, ion desorption, etc. may beevaluated.

Samples of irrigation water and tissue of the plants 109 may also beobtained and provided for analysis. Sampling protocols may be followedto ensure that the samples represent a true indication of the irrigationwater composition. Irrigation water samples may be obtained at thesource, before filtering, after filtering, and/or before addition of oneor more additives such as, e.g., nutrients and/or chemicals to form theFS 115. Composition of the irrigation water may be used as, e.g., abaseline in determining adjustments to the additive(s) for the FS 115.For example, mineral salt content may be adjusted based on the analysisof the irrigation water to meet the nutritional needs of the plants 109.Sampling protocols may also be followed to ensure that the samplesrepresent a true indication of the plant tissue composition. Planttissue samples may be leaves that are neither old nor too young such as,e.g., the first 5-6 leaves after the apex of a shoot of the plant 109.Other tissue samples include sap, stems, roots, flowers fruit, seeds,etc. that may be obtained during the growth of the plant 109. Samplingprotocols may be different for various plant materials such as, e.g.,leaf cultivation, sap, fruit, and flowers. Sampling protocols willdepend upon the species of the plant 109. Analysis of the tissue samplescan provide information of the nutritional status of the plant 109indicating absorption and/or utilization of the additives supplied inthe FS 115. Analysis may take into account evolutionary interpretationsconsidering seasonal changes of the type of plant materials and varietylevel and static interpretations without consideration of seasonalchanges.

The analysis of the soil samples, aqueous samples, irrigation watersamples, and/or plant tissue samples provides information that may beused in the evaluation of the availability, balances, intakes, and rateof use of the nutrients over the growth cycle of the plant 109. Forexample, analysis of the soil sample at each depth can provideinformation about the availability of leaching nutrients, allowingevaluation of the ion dynamics within the soil 103 (FIG. 1). Inaddition, it allows for evaluation of the rate of lixiviation of thefertilizers in the root activity zone 112 (FIG. 1) and/or the behaviorof different additives when added to the soil 103. The information maybe used, at least in part, to determine adjustments and/or changes tothe FS 115 (FIG. 1) that is applied to the soil 103 with the rootactivity zone 112.

The acquisition and analysis of aqueous samples may also be used forstatic leaching processes. For example, the process may be applied in“Heap” and “Dump” leaching for, e.g., copper lixiviation, oxidized andprimary minerals as porphidic or massive sulphides, with theparticipation of microorganisms in the catalysis of chemical reactions.In addition, monitoring and control of the soil condition may be appliedto uranium leaching, gold leaching from oxidized materials or in freeform, and/or bio-leaching of gold in sulphides minerals.

In general, static leaching processes are based on bed packedpercolation techniques, which are prepared for that purpose and may bedistinguished as two main groups: “heap leaching” and “dumpingleaching.” The difference between the two groups is based on the volume,control of the process, and the concentrations of the substances to beextracted in the solid matter. “Heap leaching” requires less time tolixiviate, lower volumes of materials, greater legal requirements, andgreater operational control. In both cases, the process is based ongaining accurate and reliable information about what happens inside thepiles during the heap and dump leaching. Three chemical phases interactin the chemical processes: solid material, the leaching agent, and gasthat is dissolved in the liquid or introduced in a forced manner.Moreover, in many cases leaching procedures count on the participationof microorganisms. These proceedings add additional information to thehistorical analysis of percolation, which allows operational measures tobe taken to correct and improve the functioning of the process.

Initially, a number of suction probes 106 are installed within the pileas described above. The number of probes 106 may be based upon thevolume and surface being examined. The suction probes 106 may besituated at various depths to obtain the widest range of informationpossible. For heap leaching, probe placement can be carried out duringconstruction. Dump leaching may also have one or more suction probe(s)106 installed during construction but, due to the longevity and longterm exploitation, suction probes 106 may be installed after the dumphas been built. This may be accomplished by forming (e.g., drilling) asmall perforation to introduce a suction probe 106. After installation,aqueous samples may be obtained using the suction probes 106 asdescribed above. The sampling schedule (and durations) may be based uponthe monitored process. The collected aqueous samples may be analyzed todetermine data such as, e.g., temperature, oxygen and other dissolvedgases, pH, electro conductivity, metal concentrations, other dissolvedcations and anions, concentration and/or types of microorganisms, and/ororganic substances produced as a result of bacterial digestions. Basedon the analysis data, recommendations may be offered in terms of, e.g.,volumes of flow, concentration of lixiviating agents, and/or air or gasflow to be injected.

The “in situ” on site monitoring may also be applied in solid-liquidextraction processes used in the cleaning and decontamination ofcontaminated lands. Applications can include metal contaminated soilclose to urban areas or other large facilities which make extraction andtransport of the contaminated soil too complicated. Examples include,but are not limited to, metallurgic facilities (smelting, steelindustry, transformers, etc.), zones with high concentrations ofminerals and metals, and/or stations or facilities where materials aretransferred, loaded or unloaded. In cases where the treatment is made insoil that has not been moved to an external waste management platform,suction probes 106 may be used to permit operational performancefollow-ups. The suction probes 106 allow for a simple implementationthat can be used for environmentally friendly monitoring. Suction probes106 may be placed and aqueous samples obtained as described above. Theinformation gained from the analysis of the aqueous samples may be usedto prove the efficiency of the applied processes and to determine anyfurther adjustments or corrections to conclude the decontamination task.

Following decontamination of soil or other degraded spaces, medium orlong term monitoring may be established using installed suction probes106. Suction probes can be placed for effective monitoring. In general,for homogenous grounds suction probes 106 are placed a various depthsfor sampling throughout the soil substrate. In non-homogenous grounds,probes 106 may be positioned to account for the soil variations. Aqueoussamples can be obtained from the probes 106 to monitor and identifypossible metabolites from substances that are not recovered completely.Samples may be analyzed to determine the behavior of substances withinthe soil and how they degrade and/or mobilize under different climaticconditions. Once the behavior is known, scheduling of measurements canbe optimized and the number of and time between each sampling may bespaced out. When fully optimized, it may be that suction probes 106 willnot provide liquid phase samples, which may indicate good functioning ofthe monitored system and a lack of a liquid phase in the activity zone.Whenever the situation changes, a gathered sample may be analyzed andthe parameters associated with the origin of the contamination.Corrective actions may be proposed based at least in part upon theanalysis results, followed by additional monitoring and testing.

Suction probes 106 may also be installed and used to provide alertsand/or prevent leaks and spoilages in processes where barriers are usedto protect surrounding environments. In situations where there is a riskof spoilage or possible transfer of products or residues to the ground,early detection of seepage into the surrounding soil can allow for arapid response.

For example, monitoring may be applied in industrial facilities withrisk of leakage or losses such as, e.g., “heap” and/or “dump” leachingof different metals (e.g., copper, uranium, gold, nickel, or others),dumping sites for hazardous wastes, urban garbage dumps or sites, and/orchemical industrial areas with pools or ponds. The use of artificialprotection barriers and/or highly impermeable layers in combination withmonitoring with suction probes 106 reduces the chance of economic lossor negative environmental impact. The configuration and extent of thebarrier used can be taken into consideration to determine the placementof suction probes 106. The suction probes 106 may be vertically situatedoutside the barrier at one or more depths and/or one or more angles ofinclination. A sampling schedule may be defined detailing the frequencyand analysis of aqueous samples obtained from the suction probes 106.Immediate notification may be provided to an operator upon detection ofan aqueous sample. A protocol may define the type of reporting whenthere is an aqueous sample as well as when no aqueous solution ispresent for sampling. Analysis of the aqueous sample can be used todetermine if the leak is a similar composition to the substances used bythe facility. In some cases, corrective measures may be recommendedbased at least in part upon the analysis results.

Referring to FIG. 3, shown is a flow chart illustrating an example ofmonitoring and control of the soil condition according to variousembodiments of the present disclosure. Beginning with block 303, one ormore suction probes 106 (FIG. 1) may be installed at one or more depthsin the soil substrate 103 (FIG. 1). The soil substrate 103 may include aroot activity zone 112 (FIG. 1) of a plant species in the soil substrate103. One or more of the suction probe(s) 106 may be within the rootactivity zone 112. The suction probes 106 include porous capsules 203(FIG. 2) that allow for hydraulic conduction of aqueous solutions fromthe soil substrate 103 and/or root activity zone 112 when a vacuum isdrawn. Holes may be drilled into the soil substrate 103 and one or moresuction probe(s) 106 inserted at one or more depths. Samples of the soilsubstrate 103 may also be obtained at a variety of depths at this timeand analyzed to determine the composition of the soil substrate 103. Inblock 306, a fertilizer solution 115 (FIG. 1) may be supplied to theplants 109 (FIG. 1) by irrigating with, e.g., a drip line or asprinkler. A sample of the FS 115 may also be collected over a portionof the entire irrigation period in block 306.

Samples are obtained in block 309. For instance, a sample (or samples)of aqueous solution(s) may be obtained from the suction probe(s) 106(FIG. 1). A vacuum is drawn on each suction probe 106 to inducehydraulic conduction of aqueous solutions from the soil substrate 103and/or root activity zone 112 (FIG. 1). After a predefined time period(e.g., 48 hours), one or more sample(s) of the aqueous solution isextracted from the suction probe(s) 106 and provided for analysis inblock 312. The aqueous samples may be analyzed for pH; electricalconductivity; anions such as, e.g., NO₃ ⁻, H₂PO₄ ⁻, HCO₃ ⁻, CO₃ ⁼, SO₄⁼, and/or Cl⁻, cations such as, e.g., Ca⁺⁺, Mg⁺⁺, K⁺, Na⁺, and/or NH₄ ⁺;and microelements such as, e.g., B, Fe, Mn, Cu, Zn, Mo, and/or Urea. Asample of the FS 115 collected over the irrigation period may also beobtained from a collection device in block 309 and the compositionanalyzed in block 312. Plant tissue samples and/or an irrigation watersample may also be obtained in block 309 and analyzed in block 312. TheFS sample, as well as an irrigation water sample, may be analyzed forthe same elements as the aqueous solutions. The tissue sample may beanalyzed for, e.g., nitrogen, phosphorous, sulfur, chlorine, calcium,magnesium, sodium, potassium, boron, iron, manganese, copper, zinc,and/or molybdenum.

In block 315, the chemical composition and/or the nutrient utilizationare evaluated based at least in part upon the sample analysis of block312. Chemical, mineral, and/or nutrient levels in the root activity zone112 (FIG. 1) may be examined and compared to predefined levelsassociated with the plant species. In some implementations, the levelsused for comparison may vary with the phenological stage of the plant109. Concentrations of marker ions (which are present in the rootactivity zone 112 but are generally not absorbed by the plant 109) suchas, e.g., chlorides and/or sodium at the different depths may also beexamined and used to evaluate, e.g., crop absorption of water andevaporation effect. In addition, ion concentrations with respect to oneor more marker ions may be used to evaluate the utilization of variousnutrients. For example, chlorides may be used to determine utilizationof nitrogen and/or other anions such as, e.g., NO₃ ⁻, H₂PO₄ ⁻, and SO₄⁼, sodium may be used to determine utilization of potassium, calcium,magnesium and/or other cations such as, e.g., NH₄ ⁺, and the combinationof chlorides and sodium (e.g., the average of both) may be used todetermine utilization of phosphorous or other chemicals and/ornutrients. Based at least in part upon the utilization, consumption ofthe ions, chemicals, and/or nutrients may also be determined. Effects ofthe soil composition may also be taken into account during theevaluations. Also, plant tissue analysis may also be used to evaluatethe absorption and/or utilization of nutrients by the plants. Theevaluation may also take into account variations in the analyzed sampleobtained over the growth of the plants as well as those obtained atdifferent locations within the field. In some cases, analysisinformation may be compared with broader agricultural segmentinformation during the evaluation.

Corrective (or remedial) measures are provided in block 318 based atleast in part upon the evaluation of block 315. For example, correctivemeasures may include increasing the water dosage to dilute the ions inthe root activity zone 112 and/or the soil substrate 103. In someimplementations, corrective measures may include irrigation of theplants 109 using irrigation water without the addition of otheradditives such as, e.g., fertilizers or chemicals. In other cases, theamount of additive(s) to be included in the FS 115 or adjustments toproportions between the chemical components in the FS 115 may beprovided. In some implementations, the corrective measures may beautomatically applied to the next application of FS 115. In someimplementations, other factors may also be considered when determiningcorrective measures. For example, weather conditions (e.g., temperature,rainfall, wind, etc.) and applied fertilization strategies (e.g., UF,fractionation, anticipate DFR, etc.) may be accounted for.

The flow chart repeats the monitoring and control of the soil conditionby returning to block 306 where another FS 115, which is based upon theadjustments provided in block 318, is again supplied to the plants 109.In this way, the condition of the soil may be monitored and controlledin a cyclic or continuous manner to improve crop growth and production.

FIG. 4 illustrates examples of the composition evaluation that may becarried out on various obtained samples in block 315 (FIG. 3). Forexample, analysis of a sample of the irrigation water 403 may provideinformation 406 including, e.g., pH level, electrical conductivity (CE),mineral contributions, bicarbonates, salty ions, etc. In addition,analysis of the FS 115 may provide information 409 about the irrigationwater 406 may include, e.g., pH level, electrical conductivity (CE), thecontribution of additives such as, e.g., chemicals and/or nutrients onthe irrigation solution, etc. Soil solutions 412 (e.g., aqueoussolutions and/or soil samples) may also be analyzed to determine soilcomposition information 415 such as, e.g., chemical and/or nutrientabsorption, leaching, pH level, electrical conductivity (CE), salinitylevels, etc. Samples of the plant 109 may also be obtained for foliaranalysis 418 which may be used to diagnose the nutritional status 421 ofthe plant 109.

Each condition of the obtained samples may be analyzed and evaluatedindividually or in conjunction with conditions of the same or othersamples in block 315 (FIG. 3) to determine the corrective measures ofblock 318 (FIG. 3). For example, pH level may be evaluated throughoutthe root activity zone 112 of the plants 109 to quantify the acidity ofthe soil substrate 103 (FIG. 1) and determine corrective solutions ifneeded. In general, pH levels are maintained in a range of about 6-8,about 6.5-8, or about 6.5-7.5 by adjusting the composition of thesupplied FS 115 (FIG. 1). Lower pH levels can pose a risk by increasingthe solubility of metals such as, e.g., Al, Mn, Fe, Cu, and Zn. A pH<5could produce Al and Mn concentrations that may be toxic. Higher pHlevels reduce the solubility of metals, but may need to use chelatingagents for Mn, Fe, and Zn. For example, EDTA may be used for a pH<6.7,DTPA may be used for a pH between 6.7 and 7.8, and EDDHA may be used fora pH>7.8. Conditions based upon the analysis of the soil samples mayalso be considered when evaluating the effect of the FS 115 on pHlevels.

The salinity condition throughout the root activity zone 112 may also beevaluated based upon, e.g., electrical conductivity (EC) and chlorideand sodium content within the aqueous samples to provide an indicationof salts and/or fertilizer accumulation and salt leaching in the rootactivity zone 112. Criteria to evaluate the EC throughout the rootactivity zone 112 will depend on the plant species. An example ofgeneral criteria that may be used to evaluate the chloride and Naconcentration ratios is provided in TABLE 1 below. The chlorideconcentration ratio (CR_(Cl)) is the ratio of the average CI level inthe aqueous samples from throughout the root activity zone 112 to the CIlevel in the supplied FS 115 and the sodium concentration ratio(CR_(Na)) is the ratio of the average Na level in the aqueous samplesfrom throughout the root activity zone 112 to the Na level in thesupplied FS 115.

TABLE 1 Cl level Cl concentration ratio (meq/l) Low Medium High <3 <1.51.5-2  ≥2 ≥3 <1.2 1.2-1.5 ≥1.5 Na level Na concentration ratio (meq/l)Low Medium High <3 <1.5 1.5-2  ≥2 ≥3 <1.2 1.2-1.5 ≥1.5

The concentration ratio may also be applied to other ions, chemicals,and/or nutrients within the root activity zone 112 and the FS 115. Forexample, the concentration ratio for an ion, chemical, or nutrient X inan aqueous sample may be expressed as:CR _(X) =X _(AS) /X _(FS)where X_(AS) is the average level of the ion, chemical, or nutrient X inthe aqueous samples from the various depths of the root activity zone112 and X_(FS) is the level of the ion, chemical, or nutrient X in thesupplied FS 115.

The EC concentration ratio (CR_(EC)) may also be used to evaluatesalinity conditions within the root activity zone 112. The CR_(EC) isthe ratio of the average EC level in the aqueous samples from throughoutthe root activity zone 112 to the EC of the supplied FS 115. When theCR_(EC) is about 1-1.2, this can indicate that the soil 103 is verypermeable. In this case, CR_(Cl) and CR_(Na) being about 1-1.2 canindicate low plant activity and/or high drainage. When CR_(Cl) andCR_(Na) are >1.5, this can indicate high plant activity and/or limiteddrainage. If the EC decreases progressively with depth, this mayindicate a strong response from the plant root system (absorption) thatis reducing salts from the root activity zone 112. In the case where theCR_(EC) indicates low permeability (>1.5), salts are entering the rootactivity zone 112 faster than they are removed by the plant roots ordrained from the root activity zone 112. High root absorption may beindicted by high rates of fertilizer use while low plant activity may beindicated by low rates of fertilizer use.

Crop development and productivity can be limited by the high salinelevels indicated by high EC. If high levels of Cl⁻ and Na⁺ are present,there is a risk of phytotoxicity, antagonism, osmotic stress, and soilpeptization. Washing irrigations and maintaining the soil moisture atfield capacity can reduce the concentrations, however Cl⁻/NO₃ ⁻ andNa⁺/(K⁺+Ca⁺⁺+Mg⁺⁺) ratios should to be accounted for by maintaining theratios at 1 (maximum). If high levels of SO₄ ²⁻, Ca⁺⁺, and Mg⁺⁺ arepresent, then the irrigation is basically osmotic and washingirrigations and maintaining the soil moisture at field capacity isneeded. High Ca⁺⁺ and Mg⁺⁺ levels can antagonize K⁺ absorption and H₂PO₄⁻ precipitation, so an increase in these nutrient supplies is desirable.Where a mix of both conditions is present, a mix of corrective measuresmay be used. Acceptable salinity levels and/or limits can vary basedupon the plant species and corrective measures may be determinedaccordingly.

Macronutrients such as, e.g., phosphorous, nitrogen, potassium, calcium,and magnesium may also be analyzed and evaluated for availability and toidentify nutrient imbalances and risks of fertilizer leaching.Concentration ratios (CR) may be determined based upon one or more ionlevels in the aqueous samples and FS 115. A utilization rate (UR) of thenutrients with respect to a marker ion may also be determined based atleast in part upon the corresponding CRs. For an ion, chemical, ornutrient X, the utilization rate may be expressed as:UR _(X)=(1−(X _(AS)/(X _(FS) ×CR _(MKR))))×100where X_(AS) is the average level of the ion, chemical, or nutrient X inthe aqueous samples from the various depths of the root activity zone112, X_(FS) is the level of the ion, chemical, or nutrient X in thesupplied FS 115, and CR_(MKR) is the concentration ratio of the markerion(s) such as, e.g., chlorides and/or sodium. A consumption index (CI)of the nutrients may also be determined based at least in part upon thecorresponding URs. For an ion, chemical, or nutrient X, the consumptionindex may be expressed as:CI _(X)=(UR _(X)/100)×X _(FS).

The UR_(X) and CI_(X) of the ion, chemical, or nutrient X may be used askey indicators in the evaluation. For example, the UR_(X) and CI_(X) maybe compared with predefined levels or ranges to determine if correctionsmay be recommended.

For phosphorous, the condition of H₂PO₄ ⁻ may be examined. In theaqueous samples from the root activity zone 112, H₂PO₄ ⁻<10 ppm canindicate low availability, H₂PO₄ ⁻ in the range of 10-20 ppm canindicate medium availability, and H₂PO₄ ⁻>20 ppm can indicate highavailability. In the FS 115, H₂PO₄ ⁻<20 ppm can provide a lowcontribution, H₂PO₄ ⁻ in the range of 20-40 ppm can provide a mediumcontribution, and H₂PO₄ ⁻>40 ppm can provide a high contribution. TheH₂PO₄ ⁻ level in the FS 115 should not be higher than 10% of the NO₃ ⁻level. The utilization rate and consumption index for phosphorous may bedetermined based upon the levels of H₂PO₄ ⁻. Broadcast fertilization maybe periodically applied with H₂PO₄ ⁻<6 ppm.

For nitrogen, the condition of NO₃ ⁻, NH₄ ⁺ and Urea may be analyzed andevaluated. In the aqueous samples from the root activity zone 112, NO₃⁻<2 meq/l can indicate low availability, NO₃ ⁻ in the range of 2-4 meq/lcan indicate medium availability, and NO₃ ⁻>4 meq/l can indicate highavailability. A high NO₃ ⁻ level at the bottom of the root activity zone112 may indicate a risk of leaching. The nitrogen utilization rate(UR_(N)) may also be considered where:UR _(N)=(1−(N _(AS)/(N _(FS) ×CR _(Cl))))×100where N_(AS) is the average level of N within the root activity zone112, which may be estimated as the average of NO₃ ⁻+NH₄ ⁺+ Urea in theaqueous samples at each depth, N_(FS) is the level of N in the FS 115estimated by the average of NO₃ ⁻+NH₄ ⁺+ Urea, and CR_(Cl) is theconcentration ratio of the chloride marker ion. A UR_(N)<33% canindicate a low use (e.g., excessive contribution or low activity duringthe period), UR_(N) in the range of 33-66% ppm can indicate a medium use(e.g., adequate contribution), and UR_(N)>66% can indicate a highcontribution (e.g., a high activity period or insufficientcontribution). The nitrogen consumption index may also be determinedwhere:CI _(N)=(UR _(N)/100)×N _(FS).The CI_(N) may also be evaluated based upon predefined levels or ranges.

An example of general criteria that may be used to evaluate the nitrogenand chloride ratio is provided in TABLE 2 below. Indications of NH₄ ⁺concentrations >0.3 meq/l may be an indication of an incipient reducingenvironment that can lead to root suffocation problems. Reducingenvironments may be corrected by, e.g., reduction of FS doses, pulseirrigation, or application of strong oxidizing chemicals such as, e.g.,potassium permanganate and/or others.

TABLE 2 Cl level N/Cl⁻ ratio meq/l Low Adequate Fertilizer <5 <1 ≥1Solution >5 <1 ≥1 Aqueous <5 <0.75 ≥0.75 Solution >5 <0.5 ≥0.5

For potassium, the condition of K⁺ may be analyzed and evaluated. In theaqueous samples from the root activity zone 112, a level of K⁺<0.3 meq/lcan indicate low availability, K⁺ in the range of 0.3-0.6 meq/l canindicate medium availability, and K⁺>0.6 meq/l can indicate highavailability. In the FS 115, K⁺<0.75 meq/l can provide a lowcontribution, K⁺ in the range of 0.75-1.5 meq/l can provide a mediumcontribution, and K⁺>1.5 meq/l can provide a high contribution. Thepotassium utilization rate (UR_(K)) may also be considered where:UR _(K)=(1−(K _(AS)/(K _(FS) ×CR _(Cl))))×100where K_(AS) is the average level of K⁺ in the aqueous samples at eachdepth in the root activity zone 112, K_(FS) is the level of K⁺ in the FS115, and CR_(Cl) is the concentration ratio of the chloride marker ion.A UR_(K)<33% can indicate a low use (e.g., excessive contribution or lowactivity during the period), UR_(K) in the range of 33-66% ppm canindicate a medium use (e.g., adequate contribution), and UR_(K)>66% canindicate a high contribution (e.g., high activity period or insufficientcontribution). The potassium consumption index may also be determinedwhere:CI _(K)=(UR _(K)/100)×K _(FS).The CI_(K) may also be evaluated based upon predefined levels or ranges.

In addition, the ratio of K⁺ with respect to other cations (or anions),which may affect utilization of K⁺ by the plant 109, may be examined.For example, the ratio of K⁺/(Na⁺+Ca⁺⁺+Mg⁺⁺) may also be evaluated. Anexample of general criteria that may be used to evaluate the level ofNa⁺+Ca⁺⁺+Mg⁺⁺ and the K⁺ ratio is provided in TABLE 3 below.

TABLE 3 Na⁺ + Ca⁺⁺+ Mg⁺⁺ level K⁺/(Na⁺ + Ca⁺⁺ + Mg⁺⁺) level meq/l LowAdequate Fertilizer <7 <0.2 ≥0.2 Solution >7 <0.15 ≥0.15 Aqueous <10<0.15 ≥0.15 Solution >10 <0.1 ≥0.1

For calcium, the condition of Ca⁺⁺ may be analyzed and evaluated. In theaqueous samples from the root activity zone 112, Ca⁺⁺<3 meq/l canindicate low availability, Ca⁺⁺ in the range of 3-4 meq/l can indicatemedium availability, and Ca⁺⁺>4 meq/l can indicate high availability.The calcium utilization rate:UR _(Ca)=(1−(Ca _(AS)/(Ca _(FS) ×CR _(Na))))×100and/or calcium consumption index:

CI_(Ca)=(UR_(Ca)/100)×Ca_(FS).

may also be considered, where Ca_(AS) is the average level of Ca⁺⁺ inthe aqueous samples at each depth in the root activity zone 112, Ca_(FS)is the level of Ca⁺⁺ in the FS 115, and CR_(Na) is the concentrationratio of the sodium marker ion. The UR_(Ca) and/or CI_(Ca) may beevaluated based upon predefined levels or ranges.

In addition, the ratio of Ca⁺⁺ with respect to other cations (oranions), which may affect utilization of Ca⁺⁺ by the plant 109, may beexamined. For example, the ratios of Ca⁺⁺/Na⁺ and Ca⁺⁺/Mg⁺⁺ may also beevaluated. Examples of general criteria that may be used to evaluate theratios are provided in TABLES 4 and 5 below.

TABLE 4 Na⁺ level Ca⁺⁺/Na⁺ ratio meq/l Low Adequate Fertilizer <3 <1 ≥1Solution >3 <0.75 ≥0.75 Aqueous <4 <1 ≥1 Solution >4 <0.75 ≥0.75

For magnesium, the condition of Mg⁺⁺ may be analyzed and evaluated. Inthe aqueous samples from the root activity zone 112, Mg⁺⁺<1.5 meq/l canindicate low availability, Mg⁺⁺ in the range of 1.5-2 meq/l can indicatemedium availability, and Mg⁺⁺>2 meq/l can indicate high availability.The magnesium utilization rate:UR _(Mg)=(1−(Mg _(AS)/(Mg _(FS) ×CR _(Na))))×100and/or magnesium consumption index:CI _(Mg)=(UR _(Mg)/100)×Mg _(FS).may also be considered, where Mg_(AS) is the average level of Mg⁺⁺ inthe aqueous samples at each depth in the root activity zone 112, Mg_(FS)is the level of Mg⁺⁺ in the FS 115, and CR_(Na) is the concentrationratio of the sodium marker ion. The UR_(Mg) and/or CI_(Mg) may beevaluated based upon predefined levels or ranges.

In addition, the ratio of Mg⁺⁺ with respect to other cations (oranions), which may affect utilization of Mg⁺⁺ by the plant 109, may beexamined. For example, the ratio of Ca⁺⁺/Mg⁺⁺ may also be evaluated. Anexample of general criteria that may be used to evaluate the ratio isprovided in TABLE 5 below.

TABLE 5 Ca⁺⁺ level Ca⁺⁺/Mg⁺⁺ ratio meq/l Low Adequate Fertilizer <5 <3≥3 Solution >5 <2 ≥2 Aqueous <6 <3 ≥3 Solution >6 <2 ≥3

Microelements (or micronutrients) such as, e.g., iron, manganese, zinc,copper, boron, etc. may also be analyzed and evaluated for availabilityand to identify toxicity risks and nutrient imbalances. An example ofgeneral criteria that may be used to evaluate microelements in the rootactivity zone 112 and FS 115 is provided in TABLE 6 below.

TABLE 6 Fe Mn Zn Cu B (ppm) (ppm) (ppm) (ppm) (ppm) Low <0.7 <0.5 <0.5<0.25 <0.15 Medium 0.7-3 0.5-2 0.5-2 0.25-1 0.15-0.6 High >3 >2 >2 >1>0.6 

The effect(s) of nutrients in the FS 115 on the plant 109 is alsoconsidered when determining a corrective measure such as adjustingnutrient levels in the FS 115 for the next application. FIG. 5illustrates the relationship between added nutrients and their effect inthe plant 109. The absorption synergies of the nutrients may also betaken into account when determining the corrective measure of block 318(FIG. 3). An example of the synergies between the nutrients is providedin TABLE 7 below.

TABLE 7 Reduces the Increases the Assimilation of: assimilation of:assimilation of: NH₄ ⁺ Mg, Ca, K, Mo Mn, P, S, Cl NO₃ ⁻ Fe, Zn Ca, Mg,K, Mo P Cu, Zn Mo K Ca, Mg Mn (acidic soils) Ca K Mn (basic soils) MgCu, Zn Mo Fe Cu, Zn Mo Cu Zn, Ca, Mo Mn

Evaluation of the conditions for determination of the appropriatecorrective measures may vary based upon plant species. For example,fruits and vegetables may flourish under very different nutrientconditions. In addition, the tolerance of the plant 109 to various ion,chemical and/or nutrient concentrations may also affect the proposedcorrective measures. Appendix A includes examples of evaluationguidelines for peach and nectarine plant species. Appendix A includesguidelines for evaluation of irrigation water quality, foliar (planttissue), FS and aqueous soil samples. In addition, Appendix A outlinesallocation of irrigation according to the growth cycle for both youngand adult plants and includes diagnosis and observed corrections basedupon aqueous sample evaluation. Correction factors are determined basedupon various evaluated conditions to determine the irrigationallocation. The amount of one or more additive(s) may be further refinedbased upon the chemical composition of the aqueous samples and theirrigation water.

Monitoring and control of the soil conditions may be implemented as anapplication executable by a computing device. For example, evaluation ofthe analyzed samples (block 315 of FIG. 3), as well as determination andprovision of corrective measures (block 318 of FIG. 3), may beimplemented with a soil monitoring and control application. Correctivemeasures may be determined based at least in part upon evaluation of theanalyzed samples using pattern recognition, neural network evaluation,and/or other rule based identification methods as can be appreciated. Inaddition, supplying a fertilizer solution (FS) (block 306 of FIG. 3),obtaining samples (block 309 of FIG. 3), and/or analyzing the samples(block 312 of FIG. 3) may be automated and controlled by the soilmonitoring and control application. The soil monitoring and controlapplication may also allow access to stored analysis data throughgenerated network pages or other graphical displays.

Appendix B includes examples of graphical displays that may be renderedfor use by a user of the soil monitoring and control application. Thegraphical displays may allow the user to access the chemical and/ornutritional monitoring of monitored crops by accessing, e.g., userprofiles, evolutionary dynamics, phytomonitoring, comparison of plotinformation, and benchmarking. Evolutionary dynamics allow the user tomonitor changes or patterns in various chemical and/or nutrientconcentrations in the aqueous samples (soil solution), plants, fruit, orother contributing factors such as, e.g., irrigation and fertilization.Upper and lower limits may be included as guidelines in the graphicalrepresentations. These limits may vary over the life cycle of the plantspecies. Comparison of plots (or monitored areas) allows correctivemeasures to be tailored for each monitored area. Phytomonitoring allowsthe user to compare the effects of multiple parameters to othermonitored environmental conditions. As indicated in Appendix A, theallocation of irrigation can vary with the crop cycle of the plantspecies as well as with the age of the plant.

Evaluation results for various parameters for irrigation water, soilcomposition, and plants may also be presented for user access. Theevaluation results may also include corrective measures as discussedabove, which are identified based upon the evaluation results. Forexample, the soil monitoring and control application may provide one ormore additives for addition to the irrigation water to improve thechemical composition of the root activity zone to increase growth andproductivity. A user may also access client databases to evaluatehistorical data. One or more monitored parameter(s) may be selected forrendering. The historical information may be displayed as a spread sheetor may be rendered in one of a plurality of graphical formats.

In addition, a variety of reports may be generated by the soilmonitoring and control application. For example, automaticinterpretations of the sample analysis may be provided in a report suchas, e.g., nutritional analysis of the root activity zone as shown inAppendix C. Such a report can include profile information related to,e.g., salinity, pH, nutritional/chemical composition, and micro and/ormacro elements. The report may also include corrective actions that maybe implemented to restore and/or maintain the chemical composition ofthe soil substrate in balance. For example, the report may indicatesuitable washes and/or additive(s) for application to the soilsubstrate. The report may also include the amount of additive(s) thatshould be added to irrigation water, based at least in part upon theresults of the aqueous solution analysis, to restore a desirablechemical/nutritional composition to the root activity zone and/or soilsubstrate. The amount of additive(s) may be based upon the evaluatedlevels of ions, chemicals, and/or nutrients. For example, a table ordatabase may provide a recommended amount based at least in part uponthe concentration levels, concentration ratio (CR), utilization rate(UR), and/or consumption index (CI). In other implementations, therecommended amount may be determined based at least in part upon theevaluations of the concentration levels, CR, UR, and/or CI using patternrecognition, neural network evaluation, and/or other rule basedidentification methods as can be appreciated.

Referring next to FIG. 6, shown is a flow chart illustrating an exampleof the evaluation that may be carried out in block 315 of FIG. 3.Chemical composition, concentration ratio (CR), utilization rate (UR),and/or consumption index (CI) can be evaluated based at least in partupon the sample analysis of block 312 (FIG. 3). Each condition of theobtained samples may be analyzed and evaluated individually or inconjunction with conditions of the same or other samples to determinethe corrective measures of block 318 (FIG. 3). Beginning with block 603,a plant species is determined for the evaluation of the analyzedsamples. For example, a user may identify the species of the plant 109(FIG. 1) through a user interface or the species may be determined basedupon information associated with the obtained samples or the locationthe samples were obtained from (e.g., from a user profile stored in adata store). The stage in the growth cycle of the identified plantspecies is determined in block 606. For example, the stage in the growthcycle may be based upon the current time of the year. The growth cyclemay be defined in terms of different growth stages during the growingseason at the location of the plant species. In some implementations,the growth cycle is defined by the month of the year. Months in whichthe plant species are dormant may not be considered. The stage of thegrowth cycle may also be adjusted based at least in part upon thematurity of the plant (e.g., a young plant or adult plant). The age ofthe plant may also be determined.

Results of the analysis of the aqueous samples, plant tissue samples,fertilizer solution (FS) samples, and/or irrigation water samples may beused in the evaluation of the availability, balances, intakes, and rateof use of the nutrients over the growth cycle of the plant 109. Forexample, in block 609 the analysis results of the aqueous samples may beevaluated to determine the condition of the root activity zone 112 (FIG.1). Chemical, mineral, nutrient, ion, and/or conductivity levels of theaqueous samples may be examined and compared to predefined levelsassociated with the plant species. The predefined levels may define twoor more ranges. The ranges may be defined for an average level of thechemical, mineral, nutrient, ion, and/or conductivity throughout theroot activity zone 112 or for each depth of the root activity zone 112.For instance, the predefined levels may define a desired range basedupon upper and/or lower limits. For example, the level of NO₃ ⁻ and Cl⁻within the root activity zone 112 can be examined and compared topredefined levels associated with the plant species. Tables 1 and 6illustrate examples of predefined levels for low, medium (or desired),and high ranges for some chemical compounds and microelements in theroot activity zone 112. In other implementations, a desired level may bespecified with defined upper and lower tolerances. In some cases,predefined levels may be specified for other combinations of ranges suchas, e.g., very low, low, desired, high, and very high.

In addition, concentration ratios with respect to other ions, chemicals,and/or nutrients in the aqueous samples may also be determined andevaluated. For example, the level of other combinations such as, e.g.,K⁺/Na⁺, K⁺/Mg⁺⁺, Ca⁺⁺/Na⁺, Ca⁺⁺/Mg⁺⁺, and/or NO₃ ⁻/NH₄ ⁺ within the rootactivity zone 112 may also be evaluated based upon predefined levels.Tables 2-5 illustrate examples of predefined levels for low and adequate(or desired) ranges for various ratios of ions or combinations of ions.The predefined levels for the concentrations and/or ratios may be basedat least in part upon historical data and the growth patterns of theplant species. The levels (or ranges) may be varied based at least inpart upon the growth cycle and/or maturity of the identified plantspecies. The predefined levels may change as the growth cycle moves frominitial growth to producing blooms to development and ripening of thefruit. The predefined levels may also vary with the maturity of theplant. As the plant species ages, the nutritional needs of the plantchanges. In addition, as the root depth changes the predefined levelsmay adjust for different depth levels of the root activity zone 112.

In block 612, the condition of the plant 109 may be evaluated based atleast in part upon the analysis of the plant tissue samples. Planttissue samples may be taken from, e.g., the foliage, stem, fruit,flowers, and/or roots of the plant 109 and analyzed in block 312 of FIG.3. Chemical, mineral, nutrient, and/or conductivity levels of the planttissue samples may be examined and compared to predefined levelsassociated with the plant species. Concentration ratios with respect toother ions, chemicals, and/or nutrients in the plant tissue samples mayalso be determined and evaluated. As described above, the predefinedlevels may be defined as a plurality of ranges, which may be based atleast in part upon historical data and the growth cycle of the plantspecies. The predefined levels (or ranges) may be varied based at leastin part upon where the plant tissue sample was obtained, the growthcycle, and/or maturity of the identified plant species. The growth cyclemay be defined in terms of different growth stages during the growingseason at the location of the plant species. In some implementations,the growth cycle is defined by the month of the year and may includemonths in which the plant species are dormant.

In block 615, the condition of the FS 115 (FIG. 1) is evaluated based atleast in part upon the sample analysis of block 312 (FIG. 3). Chemical,mineral, nutrient, and/or conductivity levels of the FS samples may beexamined and compared to predefined levels. Concentration ratios withrespect to other ions, chemicals, and/or nutrients in the plant tissuesamples may also be determined and evaluated. The concentrations and/orratios may be the same or different than those evaluated for the aqueoussamples. The predefined levels may define a plurality of ranges such as,e.g., a desired range based upon high and/or low level limits for someions, chemicals, nutrients, and/or microelements in the FS 115. In otherimplementations, a desired level may be specified with defined upper andlower tolerances. In some cases, predefined levels may be specified forother combinations of ranges such as, e.g., very low, low, desired,high, and very high. The predefined levels (or ranges) may be variedbased at least in part upon the growth cycle of the plant 109.

The interaction between the different conditions of the aqueous samples,the plant tissue samples, and/or FS samples in evaluated in block 618.As discussed with respect to FIG. 5, the utilization, absorption, and/orconsumption of some ions, chemicals and nutrients may be affected by theconcentration of other ions, chemicals, microelements and/or othernutrients. Different combinations of elements in the aqueous, planttissue, and FS samples may be evaluated in block 618. Key indicatorsthat may be used in the evaluation include the concentration ratio (CR),utilization rate (UR), and consumption index (CI) for various ions,chemicals, and/or nutrients. For example, the CR, UR, and/or CI may bedetermined and evaluated for one or more of anions such as, e.g., NO₃ ⁻,H₂PO₄ ⁻, HCO₃ ⁻, CO₃ ⁼, and/or SO₄ ⁼; cations such as, e.g., Ca⁺⁺, Mg⁺⁺,K⁺, and/or NH₄ ⁺; and/or microelements such as, e.g., B, Fe, Mn, Cu, Zn,Mo, and/or Urea. The UR for the anions may be determined using, e.g.,Cl⁻ as the marker ion and the UR for the cations may be determinedusing, e.g., Na⁺ as the marker ion. The CR, UR, and/or CI may also bedetermined and evaluated for one or more macronutrients such as, e.g.,phosphorous and/or nitrogen based upon one or more anions and/orcations. The CR, UR, and/or CI may be compared to predefined levelsdefining a plurality of ranges, which may be varied based at least inpart upon the growth cycle and/or maturity of the identified plantspecies.

Recommendations for corrective measures are then determined in block621. The recommendations may be determined based at least in part uponthe evaluations of the analyzed samples using, e.g., patternrecognition, neural network evaluation, and/or other rule basedidentification methods as can be appreciated. The recommendations caninclude, but are not limited to, changes to the chemical composition ofthe FS 115. The recommendations may be take into account the condition(or quality) of the irrigation water (block 624) as determined fromanalysis of irrigation water samples and/or the condition of the soil inthe activity zone 112 (block 627), which may have been determined fromthe initial samples taken during the installation of the suction probes106. Chemical, nutrient and/or ion concentrations and/or ratios ofdifferent chemicals, nutrients, or ions may be determined as describedabove. The recommendation may also account for the unused portion of thechemicals, nutrients, and/or ions that remain at the various depths ofthe root activity zone 112 and/or the portions of the chemicals,nutrients, and/or ions that are lost. Recommendation may include thecurrent condition of the chemicals, microelements, pH, electricalconductivity, and/or other nutrients in the activity zone 112, the planttissue, and/or the FS 115 as well as recommended corrections to returnthe conditions to their desired levels. The recommendations may includespecified amounts of chemicals and/or nutrients to the FS 115. Theaddition of a specific chelating agent may also be recommended basedupon the current or projected pH of the activity zone 112. In othercases, the recommendations may also include the addition of irrigationwater to the FS 115 to reduce levels of certain elements. Therecommendations may be based upon ion, chemical and nutrient levelsthroughout the root activity zone 112. In some cases, therecommendations may take into account the concentrations at differentdepths within the activity zone 112.

For example, current nitrogen levels may be compared to desired levelsat that stage in the growth cycle to determine if adjustments may berecommended. This may include comparison of concentrations at one ormore of the probe depths to determine whether the corresponding nitrogenlevels need to be adjusted. Current levels in the FS 115 can also beconsidered in the evaluation. Key indicators such as CR_(N), UR_(N),and/or CI_(N) may be determined and utilized to determine therecommendations for corrective measures to eliminate or reduce theenvironmental effects. The relationship between the analyzed levels andpredefined levels corresponding to the plant 109 may be used todetermine if the nitrogen level of the FS 115 should be adjusted byincreasing or reducing the levels of, e.g., NO₃ ⁻ and/or NH₄ ⁺. If thenitrogen is below or above the desired range, then the current conditionmay be reported and recommendations may be provided to adjust theconditions. In some cases, the amount of increase or decrease in thechemicals and/or nutrients added to the FS 115 may be determined basedat least in part upon the deviation from the desired range. In addition,the frequency of the addition may be provided.

Changes between the current and previous nitrogen levels in plantsamples from the leaves, stalks, sap, etc., as well as variations fromhistorical profiles over the growth cycle of the plant 109 may also beevaluated and used to determine the recommended adjustment. Theinteraction with other chemicals and/or nutrients and the effect onabsorption and utilization by the plant 109 may also be accounted for.For instance, the relationship between the concentrations of NO₃ ⁻ andCl⁻ can be examined to determine if the appropriate ratio exists for theplant 109. Based upon these relationships, recommendations regardingadjustments to the FS 115 may be adjusted. For example, if analysis ofthe aqueous and plant samples indicates that the nitrogen levels areabove the predefined level in the root activity zone 112 but are belowthe predefined level in the plant, the recommendation may be to maintainthe current nitrogen level in the FS 115 to ensure that the needs of theplant 109 are met. This recommendation may take into account the stagein the growth cycle and/or the historical profile of the plant 109, aswell as current pH level and electrical conductivity.

Similar evaluations may be carried out for other ions, chemicals and/ornutrients such as, e.g., phosphorus, potassium, calcium, magnesium,ammonium, chlorides, sodium, and/or microelements such as, e.g., iron,manganese, copper, zinc, boron, and/or molybdenum. Key indicators suchas CR, UR, and/or CI can be determined for one or more of these ions,chemicals and/or nutrients and utilized to determine a recommendation.The relationship between the analyzed levels and predefined levelscorresponding to the plant 109 may be used to determine if the chemicaland/or nutrient level of the FS 115 should be adjusted. The interactionwith other chemicals and/or nutrients and the effect on absorption,utilization and consumption by the plant 109 may also be accounted for.For potassium, the relationships between the concentrations of K⁺ andNa⁺ and/or K⁺ and Mg⁺⁺ can be examined to determine if the appropriateratios exist for the plant 109. For calcium, the relationships betweenthe concentrations of Ca⁺⁺ and Na⁺ and/or Ca⁺⁺ and Mg⁺⁺ can be examinedto determine if the appropriate ratios exist. For magnesium, therelationship between the concentrations of Ca⁺⁺ and Mg⁺⁺ can be examinedto determine if the appropriate ratio exists. The recommendation of onechemical and/or nutrient may be adjusted to take into account changes inthe recommendation of another chemical and/or nutrient.

If accumulation of one or more microelement(s) is detected, then anappropriate chelating agent (e.g., EDTA, DTPA, EDDHA) may berecommended, while taking into account the current and/or projected pHlevels of the root activity zone 112. Adjustment to amino acids,monoammonium phosphate, monopotassium phosphate, magnesium nitrate,and/or calcium fertilizers that are provided to the plant 109 may alsobe recommended based upon the evaluation of the analysis information.Recommendations regarding adjustments to the irrigation patterns and/oramounts may also be recommended based upon the available information.Drainage and aeration conditions may also be evaluated.

The recommendations may also take into account the locations of thedifferent samples within the field where the plants 109 are located. Forexample, adjustments to the configuration of the irrigation system maybe recommended based at least in part upon differences in the chemicaland/or nutrient levels at different locations within the field.Differences in the soil composition at different locations within thefield may also be accounted for by recommending different fertilizationsolutions 115 for use in different areas of the field. In addition,corrections to the irrigation practices may be recommended such as,e.g., increasing or decreasing the irrigation cycle. In some cases,variations in weather conditions (current and/or predicted) may also betaken into account when determining the corrective recommendations.Other cultivation operations may also be recommended based at least inpart upon the evaluation of the aqueous, plant tissue, and FS samples

Referring now to FIG. 7, shown is an example of a system 700 that may beutilized in the monitoring and control of soil conditions. The system700 includes one or more computing device(s) 703 and one or more userdevice(s) 706. The computing device 703 includes at least one processorcircuit, for example, having a processor 709 and a memory 712, both ofwhich are coupled to a local interface 715. To this end, the computingdevice(s) 703 may comprise, for example, a server computer or any othersystem providing computing capability. The computing device(s) 703 mayinclude, for example, one or more display devices such as cathode raytubes (CRTs), liquid crystal display (LCD) screens, gas plasma-basedflat panel displays, LCD projectors, or other types of display devices,etc. The computing device(s) 703 may also include, for example variousperipheral devices. In particular, the peripheral devices may includeinput devices such as, for example, a keyboard, keypad, touch pad, touchscreen, microphone, scanner, mouse, joystick, or one or more pushbuttons, etc. Even though the computing device 703 is referred to in thesingular, it is understood that a plurality of computing devices 703 maybe employed in the various arrangements as described above. The localinterface 715 may comprise, for example, a data bus with an accompanyingaddress/control bus or other bus structure as can be appreciated.

Stored in the memory 712 are both data and several components that areexecutable by the processor 709. In particular, stored in the memory 712and executable by the processor 709 are a soil monitoring and controlapplication 718 and potentially other applications. Also stored in thememory 712 may be a data store 721 and other data. The data stored inthe data store 721, for example, is associated with the operation of thevarious applications and/or functional entities described below. Forexample, the data store may include sample analysis results, correctivemeasures, and other data or information as can be understood. Inaddition, an operating system 724 may be stored in the memory 712 andexecutable by the processor 709. The data store 721 may be may belocated in a single computing device or may be dispersed among manydifferent devices.

The user device 706 is representative of a plurality of user devicesthat may be communicatively coupled to the computing device 703 througha network 727 such as, e.g., the Internet, intranets, extranets, widearea networks (WANs), local area networks (LANs), wired networks,wireless networks, networks configured for communication over a powergrid, or other suitable networks, etc., or any combination of two ormore such networks. In some embodiments, a user device 706 may bedirectly connected to the computing device 703.

The user device 706 may comprise, for example, a processor-based systemsuch as a computer system. Such a computer system may be embodied in theform of a desktop computer, a laptop computer, a personal digitalassistant, a cellular telephone, web pads, tablet computer systems, orother devices with like capability. The user device 706 includes adisplay device 730 upon which various network pages 733 and othercontent may be rendered. The user device 706 may be configured toexecute various applications such as a browser application 736 and/orother applications. The browser application 736 may be executed in auser device 706, for example, to access and render network pages 733,such as web pages, or other network content served up by the computingdevice 703 and/or other servers. The user device 703 may be configuredto execute applications beyond browser application 736 such as, forexample, e-mail applications, instant message (IM) applications, and/orother applications.

The components executed on the computing device 703 include, forexample, a soil monitoring and control application 718 and othersystems, applications, services, processes, engines, or functionalitynot discussed in detail herein. The soil monitoring and controlapplication 718 can generate network pages 733 such as web pages orother types of network content that are provided to a user device 706 inresponse to a request for the purpose of viewing stored data orrecommended corrective measures.

It is understood that there may be other applications that are stored inthe memory 712 and are executable by the processor 709 as can beappreciated. Where any component discussed herein is implemented in theform of software, any one of a number of programming languages may beemployed such as, for example, C, C++, C #, Objective C, Java, JavaScript, Perl, PHP, Visual Basic, Python, Ruby, Delphi, Flash, or otherprogramming languages.

A number of software components are stored in the memory 712 and areexecutable by the processor 709. In this respect, the term “executable”means a program file that is in a form that can ultimately be run by theprocessor 709. Examples of executable programs may be, for example, acompiled program that can be translated into machine code in a formatthat can be loaded into a random access portion of the memory 712 andrun by the processor 709, source code that may be expressed in properformat such as object code that is capable of being loaded into a randomaccess portion of the memory 712 and executed by the processor 709, orsource code that may be interpreted by another executable program togenerate instructions in a random access portion of the memory 712 to beexecuted by the processor 709, etc. An executable program may be storedin any portion or component of the memory 712 including, for example,random access memory (RAM), read-only memory (ROM), hard drive,solid-state drive, USB flash drive, memory card, optical disc such ascompact disc (CD) or digital versatile disc (DVD), floppy disk, magnetictape, or other memory components.

The memory 712 is defined herein as including both volatile andnonvolatile memory and data storage components. Volatile components arethose that do not retain data values upon loss of power. Nonvolatilecomponents are those that retain data upon a loss of power. Thus, thememory 712 may comprise, for example, random access memory (RAM),read-only memory (ROM), hard disk drives, solid-state drives, USB flashdrives, memory cards accessed via a memory card reader, floppy disksaccessed via an associated floppy disk drive, optical discs accessed viaan optical disc drive, magnetic tapes accessed via an appropriate tapedrive, and/or other memory components, or a combination of any two ormore of these memory components. In addition, the RAM may comprise, forexample, static random access memory (SRAM), dynamic random accessmemory (DRAM), or magnetic random access memory (MRAM) and other suchdevices. The ROM may comprise, for example, a programmable read-onlymemory (PROM), an erasable programmable read-only memory (EPROM), anelectrically erasable programmable read-only memory (EEPROM), or otherlike memory device.

Also, the processor 709 may represent multiple processors 709 and thememory 712 may represent multiple memories 712 that operate in parallelprocessing circuits, respectively. In such a case, the local interface715 may be an appropriate network that facilitates communication betweenany two of the multiple processors 709, between any processor 709 andany of the memories 712, or between any two of the memories 712, etc.The local interface 715 may comprise additional systems designed tocoordinate this communication, including, for example, performing loadbalancing. The processor 709 may be of electrical or of some otheravailable construction.

Although the soil monitoring and control application 718, and othervarious systems described herein, may be embodied in software or codeexecuted by general purpose hardware as discussed above, as analternative the same may also be embodied in dedicated hardware or acombination of software/general purpose hardware and dedicated hardware.If embodied in dedicated hardware, each can be implemented as a circuitor state machine that employs any one of or a combination of a number oftechnologies. These technologies may include, but are not limited to,discrete logic circuits having logic gates for implementing variouslogic functions upon an application of one or more data signals,application specific integrated circuits having appropriate logic gates,or other components, etc. Such technologies are generally well known bythose skilled in the art and, consequently, are not described in detailherein.

The flowcharts of FIGS. 3 and 6 show the functionality and operation ofan implementation of portions of a soil monitoring and controlapplication 718. If embodied in software, each block may represent amodule, segment, or portion of code that comprises program instructionsto implement the specified logical function(s). The program instructionsmay be embodied in the form of source code that comprises human-readablestatements written in a programming language or machine code thatcomprises numerical instructions recognizable by a suitable executionsystem such as a processor 709 in a computer system or other system. Themachine code may be converted from the source code, etc. If embodied inhardware, each block may represent a circuit or a number ofinterconnected circuits to implement the specified logical function(s).

Although the flowcharts of FIGS. 3 and 6 show a specific order ofexecution, it is understood that the order of execution may differ fromthat which is depicted. For example, the order of execution of two ormore blocks may be scrambled relative to the order shown. Also, two ormore blocks shown in succession in FIGS. 3 and/or 6 may be executedconcurrently or with partial concurrence. Further, in some embodiments,one or more of the blocks shown in FIGS. 3 and/or 6 may be skipped oromitted. In addition, any number of counters, state variables, warningsemaphores, or messages might be added to the logical flow describedherein, for purposes of enhanced utility, accounting, performancemeasurement, or providing troubleshooting aids, etc. It is understoodthat all such variations are within the scope of the present disclosure.

Also, any logic or application described herein, including soilmonitoring and control application 718, that comprises software or codecan be embodied in any non-transitory computer-readable medium for useby or in connection with an instruction execution system such as, forexample, a processor 709 in a computer system or other system. In thissense, the logic may comprise, for example, statements includinginstructions and declarations that can be fetched from thecomputer-readable medium and executed by the instruction executionsystem. In the context of the present disclosure, a “computer-readablemedium” can be any medium that can contain, store, or maintain the logicor application described herein for use by or in connection with theinstruction execution system. The computer-readable medium can compriseany one of many physical media such as, for example, electronic,magnetic, optical, electromagnetic, infrared, or semiconductor media.More specific examples of a suitable computer-readable medium wouldinclude, but are not limited to, magnetic tapes, magnetic floppydiskettes, magnetic hard drives, memory cards, solid-state drives, USBflash drives, or optical discs. Also, the computer-readable medium maybe a random access memory (RAM) including, for example, static randomaccess memory (SRAM) and dynamic random access memory (DRAM), ormagnetic random access memory (MRAM). In addition, the computer-readablemedium may be a read-only memory (ROM), a programmable read-only memory(PROM), an erasable programmable read-only memory (EPROM), anelectrically erasable programmable read-only memory (EEPROM), or othertype of memory device.

Briefly described, one embodiment, among others, comprises a methodincluding obtaining aqueous samples extracted from a plurality ofsuction probes positioned at multiple depths within a soil substrateincluding a root activity zone of a plant species in the soil substrate;analyzing the aqueous samples to determine a chemical composition of thesoil substrate; and determining amounts of an additive that is added toirrigation water supplied to the soil substrate to adjust the chemicalcomposition of the soil substrate based at least in part upon thedetermined chemical composition and the plant species. At least one ofthe plurality of suction probes may be positioned within the rootactivity zone. Determining the chemical composition of the soilsubstrate may comprise determining a chemical composition of the rootactivity zone.

The method may comprise determining amounts of a plurality of additivesthat are added to the irrigation water supplied to the soil substrate toadjust the chemical composition of the soil substrate based at least inpart upon the determined chemical composition and the plant species. Theadditive may comprise water, residue water, fertilizer, or anycombination thereof. The method may comprise obtaining a sample of afertilizer solution (FS) that has been supplied to the soil substrateand analyzing the FS sample to determine a composition of the FS,wherein the determined amount of additive is based at least in part uponthe determined FS composition. The FS may be supplied to the soilsubstrate at least a predetermined time before extracting the aqueoussamples from the plurality of suction probes. The sample of the FS maybe collected over an entire irrigation time during which the FS issupplied to the soil substrate.

The method may comprise extracting the aqueous samples from theplurality of suction probes. A vacuum may be drawn on each of theplurality of suction probes to induce hydraulic conduction of aqueoussolutions from the soil substrate into each suction probe. The methodmay comprise obtaining a sample of the irrigation water and analyzingthe irrigation water sample to determine a composition of the irrigationwater, wherein the determined amount of additive is based at least inpart upon the determined irrigation water composition. The method maycomprise obtaining a tissue sample of the plant species in the rootactivity zone and analyzing the plant tissue sample to determine anutritional condition of the plant. The method may comprise providingthe determined amounts of additive that is added to the irrigation waterto produce a fertilizer solution (FS) that is supplied to the soilsubstrate. The method may comprise mixing the determined amounts ofadditive with the irrigation water to produce the FS and applying the FSto the soil substrate. The FS may be applied through a drip line.

Another embodiment, among others, comprises a method includinginstalling a suction probe at a depth within a soil substrate; drawing avacuum on the suction probe to induce hydraulic conduction of aqueoussolutions from the soil substrate into the suction probe; extracting anaqueous sample from the suction probe after applying the vacuum for apredetermined period of time; and analyzing the aqueous sample todetermine a chemical composition at the depth of the soil substrate. Themethod may comprise installing a plurality of suction probes at multipledepths within the soil substrate; drawing a vacuum on each of theplurality of suction probes to induce hydraulic conduction of aqueoussolutions from the soil substrate into each suction probe; extractingaqueous samples from the plurality of suction probes after applying thevacuum for the predetermined period of time; and analyzing the aqueoussamples to determine a chemical composition at the different depths ofthe soil substrate.

The aqueous samples may be analyzed to determine chemical composition atdifferent depths of the soil substrate. At least one of the plurality ofsuction probes may be installed within a root activity zone of a plantspecies in the soil substrate. The aqueous samples may be analyzed todetermine a chemical composition of the root activity zone. The methodmay comprise determining a corrective measure based at least in partupon the determined chemical composition of the root activity zone. Thecorrective measure may be a washing irrigation. The method may compriseobtaining a plurality of soil samples at different depths of the rootactivity zone. The method may comprise determining a corrective measurebased at least in part upon the determined chemical composition of thesoil substrate.

Another embodiment, among others, comprises a method includingobtaining, by a computing device, a composition of a fertilizer solution(FS) that has been supplied to a soil substrate including a rootactivity zone of a plant species; obtaining, by the computing device, achemical composition within the root activity zone, the chemicalcomposition determined by analysis of an aqueous sample obtained from asuction probe positioned within the root activity zone after the FS issupplied to the soil substrate; determining, by the computing device,nutrient utilization by the plant species based at least in part uponthe FS composition and the chemical composition of the root activityzone; and providing, by the computing device, an amount of additive thatis added to irrigation water to produce a subsequent FS that is suppliedto the soil substrate. The method may comprise obtaining the chemicalcomposition at multiple depths within the root activity zone, thechemical composition determined by analysis of aqueous samples obtainedfrom suction probes positioned at the multiple depths of the rootactivity zone after the FS is supplied to the soil substrate.

The method may comprise obtaining the chemical composition at multipledepths within the root activity zone, the chemical compositiondetermined by analysis of aqueous samples obtained from suction probespositioned at the multiple depths of the root activity zone after the FSis supplied to the soil substrate. The method may comprise obtainingnutritional status of the plant species that is based upon analysis of atissue sample of the plant species and determining the amounts ofnutrients for the subsequent FS based at least in part upon thedetermined nutrient utilization and the nutritional status of the plantspecies. Determining nutrient utilization may include evaluating markerion concentrations determined by analysis of the aqueous sample.Determining nutrient utilization may include determining a nitrogenutilization rate and/or a potassium utilization rate.

It should be emphasized that the above-described embodiments of thepresent disclosure are merely possible examples of implementations setforth for a clear understanding of the principles of the disclosure.Many variations and modifications may be made to the above-describedembodiment(s) without departing substantially from the spirit andprinciples of the disclosure. All such modifications and variations areintended to be included herein within the scope of this disclosure andprotected by the following claims.

It should be noted that ratios, concentrations, amounts, and othernumerical data may be expressed herein in a range format. It is to beunderstood that such a range format is used for convenience and brevity,and thus, should be interpreted in a flexible manner to include not onlythe numerical values explicitly recited as the limits of the range, butalso to include all the individual numerical values or sub-rangesencompassed within that range as if each numerical value and sub-rangeis explicitly recited. To illustrate, a concentration range of “about0.1% to about 5%” should be interpreted to include not only theexplicitly recited concentration of about 0.1 wt % to about 5 wt %, butalso include individual concentrations (e.g., 1%, 2%, 3%, and 4%) andthe sub-ranges (e.g., 0.5%, 1.1%, 2.2%, 3.3%, and 4.4%) within theindicated range. The term “about” can include traditional roundingaccording to significant figures of numerical values. In addition, thephrase “about ‘x’ to ‘y’” includes “about ‘x’ to about ‘y’”.

Therefore, at least the following is claimed:
 1. A method, comprising:obtaining one or more aqueous sample extracted from at least one suctionprobe installed at one or more depth within a soil substrate; analyzingthe one or more aqueous sample to determine a chemical composition ofthe one or more aqueous sample obtained at the one or more depth of thesoil substrate, the chemical composition comprising concentrations ofnon-nutrient substances at the one or more depths of the soil substrate;and determining a corrective measure based at least in part upon thechemical composition of the one or more aqueous sample.
 2. The method ofclaim 1, wherein extraction of the one or more aqueous sample comprisesdrawing a vacuum on the at least one suction probe for a predeterminedperiod of time to induce hydraulic conduction of at least one aqueoussolution from the soil substrate into the at least one suction probe. 3.The method of claim 1, wherein the chemical composition comprisesmicroorganisms.
 4. The method of claim 1, wherein the corrective measurecomprises irrigation of the soil substrate.
 5. The method of claim 4,wherein the irrigation is a washing irrigation.
 6. The method of claim4, wherein the irrigation comprises application of an additive to adjusta chemical composition of the soil substrate to predefined levels, theadditive based at least in part upon the chemical composition of the oneor more aqueous sample.
 7. The method of claim 1, wherein the correctivemeasure comprises injection of a gas into the soil substrate.
 8. Themethod of claim 1, wherein the one or more aqueous sample comprise aplurality of aqueous samples extracted from suction probes installed atmultiple depths within the soil substrate.
 9. A method, comprising:analyzing one or more aqueous sample collected in at least one suctionprobe installed within a soil substrate to determine a chemicalcomposition of the one or more aqueous sample, the chemical compositioncomprising concentrations of non-nutrient substances of the soilsubstrate; and determining a corrective measure based at least in partupon the chemical composition of the one or more aqueous sample.
 10. Themethod of claim 9, comprising determining nutrient utilization of aplant species established in the soil substrate based at least in partupon the chemical composition of the one or more aqueous sample.
 11. Themethod of claim 10, wherein the nutrient utilization is further basedupon a composition of a fertilizer solution (FS) supplied to the soilsubstrate before obtaining the one or more aqueous sample extracted fromthe at least one suction probe.
 12. The method of claim 11, wherein thecorrective measure comprises providing an amount of additive that isadded to irrigation water to produce a subsequent FS that is supplied tothe soil substrate.
 13. The method of claim 12, wherein the amount ofadditive is based at least in part upon the nutrient utilization and anutrient status of the plant species, wherein the nutritional status isbased upon analysis of a tissue sample of the plant species.
 14. Themethod of claim 12, wherein the amount of additive is based at least inpart upon the nutrient utilization and nutritional needs of the plantspecies.
 15. The method of claim 14, wherein the amount of additive isfurther based upon a composition of the irrigation water.
 16. The methodof claim 11, wherein the FS was applied to the soil substrate at least apredetermined time before extracting the one or more aqueous sample fromthe at least one suction probe.
 17. The method of claim 11, wherein thecomposition of the FS is determined by analysis of a sample of the FS,wherein the FS comprises concentrations of plant nutrients andnon-nutrients.
 18. The method of claim 17, wherein the sample of the FSis collected over an entire irrigation time period during which the FSis applied to the soil substrate.
 19. The method of claim 10, whereindetermining nutrient utilization includes evaluating marker ionconcentrations determined by the analysis of the one or more aqueoussample.
 20. The method of claim 10, wherein determining nutrientutilization includes determining a nitrogen utilization rate or apotassium utilization rate.